The present invention relates to an improved process for the recovery of vanadium from various residues from the combustion of petroleum.
Processes according to the prior art for the recovery of vanadium from the various residues deriving from petroleum combustion are substantially of two types: those which make vanadium extraction from said residues in acid solutions, and those which instead make said extraction in a basic medium.
For the processes of the second type, a very modest basic leaching yield has been hitherto obtained with petroleum ash: for example, with a 5-10% solution of caustic soda the yield obtained was smaller or at the most equal to 60% with respect to the vanadium originally contained in the treated residues.